Question

A circular park of radius 15 m has a road 2 m wide all around inside it. Find the area of the road.​

Answer 1

$\huge{\underline{\underline{\red{Answer}}}}$

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$\mathbb{\boxed{\pink{GIVEN}}}$

• Radius=15m
• Road=2m wide

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$\bf{\underline{\underline{\red{SOLUTION}}}}$

$area \: of \: park \: without \: road \: = \pi \: {r}^{2} \\ \implies \: area = \frac{22}{7} \times 15 \times 15 {m}^{2} - - - - - - i$

Radius of park with road= 2+15m =17m

$area = \pi {r}^{2} \\ = \frac{22}{7} \times 17 \times 17$

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Area of road

= Area of park with road- Area of park without road$= (\frac{22}{7} \times 17 \times 17) - ( \frac{22}{7} \times 15 \times 15) {m}^{2} \\ = \frac{22}{7} (17 \times 17 - 15 \times 15) {m}^{2} \\ = \frac{22}{7} \times 64 {m}^{2} \\ = 22 \times 8 \\ = 176 {m}^{2}$

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